In recent years, an electronic toll collection (ETC) system has been widely used in many countries. A conventional ETC system works by insetting a contact-type integrated circuit (IC) card into an on-board unit mounted on a vehicle. The vehicle cannot pass through a tollgate of a tollroad equipped with the ETC system, if there is a poor contact between the IC card and the on-board unit, or if a driver of the vehicle forgets to insert the IC card into the on-board unit.
Japanese Patent Application No. 2006-313377 filed by the present inventors discloses a system, in which card data of an IC card is copied to an on-board unit in advance, and the copied card data is used when the vehicle passes through a tollgate. Thus, the system allows the vehicle to pass through the tollgate without the IC card so that the driver does not have to carry the IC card.
However, since an infrastructure of an ETC system has not been completed, there are manned tollgates where roadside units designed for an ETC system are not installed. At the manned tollgate, a driver of the vehicle needs to withdraw an IC card from an on-board unit and needs to pass the IC card to a tollgate attendant to pay a toll fee. Therefore, the system disclosed in Japanese Patent Application No. 2006-313377 cannot work at the manned tollgate, if the driver does not carry the IC card.
To use the system disclosed in Japanese Patent Application No. 2006-313377 at the manned tollgate, a means for transmitting the card data stored in the on-board unit to a toll collection unit installed at the manned tollgate is required. The card data can be transmitted to the toll collection unit by connecting the on-board unit and the toll connection unit with a communication cable as the means. However, various kinds of vehicles such as trucks, small cars, and motorcycles travel a tollroad, and mounting locations of the on-board units are different between the vehicles. Therefore, if the communication cable is used as the means for transmitting the card data stored in the on-board unit to the toll collection unit, it will take much time for the vehicles to pass through the manned tollgate. As a result, traffic congestion will occur at the manned tollgate.